Brumm M C, Ellis M, Johnston L J, Rozeboom D W, Zimmerman D R
Haskell Agricultural Laboratory, University of Nebraska, Concord 68728, USA.
J Anim Sci. 2001 Aug;79(8):1967-72. doi: 10.2527/2001.7981967x.
Two experiments were conducted to evaluate the possible interaction of nursery space allocations and grow-finish space allocations in swine. In Exp. 1, crowding was achieved by varying the number of pigs per pen. During the nursery phase, decreasing the space allocation (0.16 m2/pig vs 0.25 m2/pig; 8 and 12 pens per treatment, respectively) by increasing the number of pigs per pen (18 vs 12) resulted in a decrease in daily feed intake (0.609 vs 0.683 kg/d; P < 0.001) and daily gain (0.364 vs 0.408 kg/d; P < 0.001). Pigs were mixed within nursery treatment groups and reassigned to grow-finish pens (6 pens per treatment) at the end of the 35-d nursery period providing either 0.56 m2/pig (14 pigs/pen) or 0.78 m2/pig (10 pigs/pen). Crowding during the grow-finish phase decreased daily feed intake (P < 0.003) and daily gain (P < 0.001). In Exp. 2, space allocations of 0.16 m2/pig vs 0.23 m2/pig during the nursery phase (24 pens per treatment) resulted in a decrease in daily feed intake (0.612 vs 0.654 kg/d; P < 0.005) and daily gain (0.403 vs 0.430 kg/d; P < 0.001). Pigs remained in the same (social) groups when moved to the grow-finish phase. Unlike Exp. 1, there was no effect of crowding during the grow-finish phase (0.60 m2/pig vs 0. 74 m2/pig) on daily feed intake or daily gain. The difference in results between experiments suggests that the response to crowding during the grow-finish phase may depend in part on whether pigs are mixed and sorted following movement from the nursery.
进行了两项试验以评估仔猪保育阶段和生长育肥阶段空间分配之间可能存在的相互作用。在试验1中，通过改变每栏猪的数量来实现拥挤。在保育阶段，通过增加每栏猪的数量（18头对12头）来减少空间分配（每头猪0.16平方米对每头猪0.25平方米；每个处理分别为8栏和12栏），导致日采食量（0.609对0.683千克/天；P<0.001）和日增重（0.364对0.408千克/天；P<0.001）降低。在35天的保育期结束时，将保育处理组内的猪混合，并重新分配到生长育肥栏（每个处理6栏），每头猪提供0.56平方米（每栏14头猪）或0.78平方米（每栏10头猪）空间。生长育肥阶段的拥挤降低了日采食量（P<0.003）和日增重（P<0.001）。在试验2中，保育阶段每头猪0.16平方米对0.23平方米的空间分配（每个处理24栏）导致日采食量（0.612对0.654千克/天；P<0.005）和日增重（0.403对0.430千克/天；P<0.001）降低。当猪进入生长育肥阶段时，它们仍留在原来（社交）的组中。与试验1不同，生长育肥阶段的拥挤（每头猪0.60平方米对每头猪0.74平方米）对日采食量或日增重没有影响。试验结果的差异表明，生长育肥阶段对拥挤的反应可能部分取决于猪从保育阶段转出后是否进行了混合和重新分组。
